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Query: UMLS:C0028754 (obesity)
124,988 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 61-year-old woman with hyper-catecholaminemia and hyper-glucocorticoidemia due to a mixed tumor of the right adrenal gland is described. The patient, who had been medicated for hypertension since 1977, complained of thirst and general malaise in 1986. Body weight loss was remarkable. There was neither absolute truncal obesity nor moon face. In September 1986, her blood pressure was 180/110 mmHg and blood glucose level was 400mg/dl. Noradrenaline levels in plasma and in urine were remarkably elevated (1659 pg/ml and 120 micrograms/day, respectively), and adrenaline levels were also high (397 pg/ml in plasma, 34 micrograms/day in urine). Plasma cortisol and urinary 17-OHCS were elevated (39.2 micrograms/dl and 11.9 mg/day, respectively). Plasma ACTH was in the normal range (42.6 pg/ml). Oral administration of neither 1mg nor 8 mg of dexamethasone suppressed plasma cortisol or ACTH levels. Both 131I-metaiodobenzylguanidine and 131I-adosterol accumulated in the right adrenal gland. In 1987 the adrenal tumor (3.0 x 3.5 cm, 30 g) was resected. After the operation, her blood pressure and blood glucose level returned to normal, so that the medication became unnecessary. Histologically it was revealed that the tumor was a mixed adenoma consisting of adreno-medullary and cortical cells (corticomedullary adenoma). The literature on 21 cases of pheochromocytoma associated with Cushing's syndrome was briefly reviewed. Mathison (1969) reported the first case of a mixed tumor of adreno-medullary and cortical cells. So far as we know the present case is the second.
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PMID:[A case of adrenal mixed tumor of pheochromocytoma and adrenocortical adenoma presenting diabetes mellitus and hypertension]. 837 53

It has been shown that visceral obesity is associated with an increased incidence of hyperinsulinemia. In such a condition, hyperinsulinemia could be due to an increased lipolytic activity of omental adipose tissue (AT), through an enhanced portal flux of FFA. The purpose of our study was to evaluate the lipolytic activity of omental and epigastric AT obtained from morbid obese patients either with prevalently visceral or subcutaneous abdominal fat accumulation, evaluated by computerized tomography. The relationship between plasma insulin values and in vitro lipolytic activity in both tissues was studied. Thirteen visceral (VO) and 13 subcutaneous (SO) obese patients, matched for sex and body mass index, undergoing vertical banded gastroplasty, were studied. Before surgery, in each patient an OGTT was performed. During surgery, samples of epigastric subcutaneous and omental AT were obtained for evaluation of fat cell weight (FCW) and basal, noradrenaline 10(-5)M and isoprenaline 10(-5) M induced lipolytic activities. No significant differences in basal lipolysis were found between the two types of obesity, both in omental and in epigastric AT. In omental AT, a higher noradrenaline and isoprenaline induced lipolysis was observed in VO than in SO. Isoprenaline induced lipolysis of omental AT (expressed per cell surface area) correlated directly with FCW. VO patients showed plasma insulin values after OGTT significantly higher than SO patients. In the whole group of patients, independently from fat distribution, significant correlations were found between the incremental areas of the plasma insulin curve during OGTT and the noradrenaline an isoprenaline induced lipolytic activities both in omental and epigastric adipose tissue.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Omental and epigastric adipose tissue lipolytic activity in human obesity. Effect of abdominal fat distribution and relationship with hyperinsulinemia. 840 22

This study was undertaken to determine whether receptor and non-receptor components of the adenylate cyclase (AC) cascade were altered in brown adipose tissue (BAT) of 14-day-old pre-obese (fa/fa) rats, before endocrine status is strongly modified by fa gene expression. Activity of the AC catalytic subunit did not differ between the two genotypes. In fa/fa rats compared with control Fa/fa rats, there was a 50% decrease in the activity of alpha Gs (stimulated by NaF or guanosine 5'-[gamma-thio]triphosphate) but no change in protein content (Western blotting). alpha Gi function, assessed by the inhibitory action of low concentrations of guanosine 5'-[beta gamma-imido]triphosphate upon 10(-4) M forskolin-stimulated AC activity, was equally low in both genotypes. Analysis of dose-response curves for different beta-agonists revealed that (i) both the basal and the maximally stimulated activity of AC were 2-fold lower in fa/fa rats than in Fa/fa rats; (ii) BRL37344 and CGP12177 (beta 3 agonists) were less potent in fa/fa than in Fa/fa rats (Kact. multiplied by 2); (iii) noradrenaline and isoprenaline (Iso), at the low-affinity site (beta 3-AR), were less potent in fa/fa than in Fa/fa pups (Kact. increased by 30 and 20% respectively). At the high-affinity site (mainly beta 1) these two agonists were more potent in fa/fa than in Fa/fa rats (Kact. decreased by 40 and 80% respectively). In good agreement with the latter result, the beta 1-adrenergic receptor (beta 1-AR)-selective antagonist CGP20712A had more effect on the Iso-stimulated AC activity in pre-obese than in lean pups (2-fold decreased in IC50). Binding experiments with [3H]CGP12177 show that in BAT of suckling rats, beta 3-ARs represent 80% of the total beta-ARs. Bmax values for the two sites were not affected by the genotype, although the beta 3-AR mRNA concentration in BAT (quantitative reverse-transcriptase PCR) was 3-fold lower in fa/fa rats than in Fa/fa pups. In conclusion, these results provide evidence for alterations in beta 1- and beta 3-AR signalling in BAT of 14-day-old suckling pre-obese Zucker rats with a decreased activity of alpha Gs. The impaired AC responsiveness to catecholamines might be a primary contributor to the development of this genetic obesity.
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PMID:Early alterations in the brown adipose tissue adenylate cyclase system of pre-obese Zucker rat fa/fa pups: decreased G-proteins and beta 3-adrenoceptor activities. 855 20

1. In the present study, using the euglycaemic hyperinsulinaemic glucose clamp technique, we investigated the effects of hyperinsulinaemia on sodium-water metabolism and the pressor system in obesity, both of which have been reported to be closely associated with insulin resistance and/or hyperinsulinaemia. 2. Sixteen obese young subjects and 24 non-obese young subjects who were all normotensives, participated in this study. The 2 h euglycaemic hyperinsulinaemic glucose clamp was performed in a fasting state. The mean glucose infusion rate needed to maintain a fasting blood sugar level (FBS) during the last 30 min of the clamp was used as an indicator of insulin sensitivity (M-value). Before and after the clamp, the following parameters were measured: creatinine clearance (Ccr); urinary excretion of sodium (UNaV); fractional excretion of sodium (FENa); plasma renin activity (PRA); plasma aldosterone concentration (PAC) and plasma noradrenaline concentration (PNA). 3. The M-value was significantly lower in obese subjects compared with non-obese subjects, although FBS and fasting immunoreactive insulin levels were similar in both groups. UNaV and FENa fell only in obese subjects during the clamp, while Ccr showed no significant change in either group. PNA and PRA increased significantly and PAC tended to increase in both groups. 4. These results suggest that obese subjects have insulin resistance with respect to glucose metabolism, but that urinary sodium excretion and the pressor system remain insulin-sensitive; the sensitivity of the sodium retaining action to hyperinsulinaemia was actually higher in obese subjects than in non-obese subjects. Therefore, if compensatory endogenous hyperinsulinaemia was raised by insulin resistance, these two factors may lead to chronic sodium retention and pressor system stimulation and, in turn, to hypertension in obesity.
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PMID:Effects of hyperinsulinaemia on renal function and the pressor system in insulin-resistant obese adolescents. 871 63

1. The anti-obesity and anti-diabetic effects of mazindol were evaluated in obese diabetic yellow KK mice and C57Bl control mice. 2. The study compound was fed through a gastric tube at a rate of 1 or 2 mg/kg per day (0.01 mol/L HCl as control) for 2 weeks. The following parameters were compared in treated and control animals: bodyweight, food intake, white adipose tissue (WAT) weight, brown adipose tissue (BAT) weight and its thermogenesis, noradrenaline (NA) turnover, blood glucose and serum insulin levels and glucose transporter 4 (GLUT4). 3. Furthermore, bodyweight loss of mice pair-fed the same amount of food as the mazindol-treated mice for 2 weeks was measured. 4. Mazindol significantly decreased food intake and significantly increased guanosine-5'-diphosphate-binding in BAT mitochondria and NA turnover in BAT in both yellow KK and C57Bl groups. The amounts of WAT in subcutaneous, mesenteric and retroperitoneal regions and bodyweights were significantly decreased in both groups. Bodyweight loss in mice pair fed with the mazindol-treated groups was approximately 70% compared with that in the mazindol-treated groups. Furthermore, mazindol decreased the levels of blood glucose and serum insulin during the glucose overloading test in yellow KK mice, but it did not influence the GLUT4 protein concentration in WAT and muscle. 5. These observations suggest that mazindol possesses both an anti-obesity action, due to the inhibition of appetite as well as the activation of BAT thermogenesis via increased NA turnover in BAT, and an anti-diabetic action. Consequently, mazindol may be useful for the treatment of obesity as well as non-insulin-dependent diabetes mellitus in obese persons.
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PMID:Anti-obesity and anti-diabetic effects of mazindol in yellow KK mice: its activating effect on brown adipose tissue thermogenesis. 880 May 69

The beta 3-adrenergic receptor, located mainly in fat cells of visceral adipose tissue, is involved in the regulation of lipolysis and thermogenesis. Recently, a mutation in the corresponding gene resulting in the replacement of tryptophan by arginine in position 64 (Trp64Arg) has been demonstrated, which associated with obesity and metabolic complications of obesity. We have investigated whether this polymorphism is associated with changes in beta 3-adrenergic receptor function or clinical characteristics in 40 non-obese and 43 obese non-diabetic subjects who underwent elective abdominal surgery. The beta-adrenergic receptor gene polymorphism was examined by restriction-enzyme cleavage conformation. Beta 3-adrenergic receptor function was investigated by measuring lipolysis in isolated visceral white fat cells incubated with noradrenaline (natural ligand) or (CGP) 12,177 (selective beta 3-agonist). No homozygotes for the mutation were found. The allelic frequency of Trp64Arg was similar in obese and non-obese subjects (9.4 and 12.5%, respectively). In obese and non-obese subjects there was no change in body mass index, body fat distribution, fat cell size, fasting circulating levels of insulin, glucose or lipids, blood pressure or adipocyte lipolysis induced by noradrenaline or CGP 12,177 when Trp64Arg heterozygotes were compared with Trp64A homozygotes. Our results suggest that the Trp64Arg mutation in its heterozygous form is not a major determinant of beta 3-adrenergic receptor function (when assessed by lipolysis in white adipose tissue) or of the pathophysiology of obesity.
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PMID:Phenotypic characterization of the Trp64Arg polymorphism in the beta 3-adrenergic receptor gene in normal weight and obese subjects. 881 12

In this study we investigated whether fat cell lipolysis could be involved in the aetiology of obesity by comparing non-obese subjects with (Hob) or without (Hnorm) a family trait for overweight. A family history of obesity was present when at least one of the first-degree relatives had body mass index of 27 kg/m2 or more. Twenty-seven healthy, drug-free non-obese adult subjects were investigated; 13 were Hob and the remaining 14 were Hnorm. Eleven Hob had at least one obese parent. Isolated fat cells from abdominal subcutaneous adipose tissue were incubated in vitro. Glycerol release (lipolysis index), mRNA levels and enzymatic activity of hormone-sensitive lipase and radioligand binding to beta 1- and beta 2-adrenoceptors were determined. The lipolytic effects of noradrenaline (major endogenous lipolytic agent), isoprenaline (a non-selective beta-adrenoceptor agonist), forskolin (a direct activator of adenylyl cyclase) and dibutyryl cyclic AMP (activating protein kinase and thereby hormone-sensitive lipase) were reduced by about 50% (p from 0.001 to 0.01). The maximum activity of hormone-sensitive lipase was reduced 50% in Hob (p < 0.05) and correlated with the lipolytic responsiveness of fat cells in the whole population (r = 0.71). However, there was no difference between the groups in steady-state mRNA levels for the enzyme. Beta 1-->, beta 2- and alpha 2-adrenoceptor sensitivity as well as beta 1- and beta 2-adrenoceptor numbers were normal in Hob. Fasting plasma insulin was 49.1 and 32.6 pmol/l, respectively in Hob and Hnorm (p = 0.01). There was, however, no significant correlation between lipolysis in vitro and plasma insulin. Thus, lipolytic catecholamine resistance in fat cells, at least partly due to impaired function of hormone-sensitive lipase, is an adipocyte abnormality associated with a family tendency to obesity.
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PMID:Adipocyte lipolysis in normal weight subjects with obesity among first-degree relatives. 885 14

Sibutramine is a noradrenaline and 5-hydroxytryptamine reuptake inhibitor which causes weight loss in laboratory rodents via effects on both food intake and metabolic rate. Sibutramine's effects are predominantly mediated by two pharmacologically-active metabolites (its primary and secondary amines). Sibutramine and its active metabolites do not cause the release of monoamine neurotransmitters and do not have affinity for their receptors. Sibutramine dose-dependently inhibits 24 h food intake in rats by enhancing the natural physiological process of satiety. Sibutramine also stimulates thermogenesis in rats, producing sustained (> 6 h) increases in oxygen consumption of up to 30%. The thermogenic effect of sibutramine results from central activation of efferent sympathetic activity which, in turn, involves activation of beta 3-adrenoceptors. Sympathetic stimulation of brown adipose tissue via beta 3-adrenoceptors is thought to be the cause of the large, 18 fold increase in brown adipose tissue glucose utilization induced by sibutramine. These dual effects of sibutramine on food intake and thermogenesis explain its anti-obesity effect in animals.
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PMID:Sibutramine: a review of the pharmacology of a novel anti-obesity agent. 913 38

The beta 3 subtype of adrenaline and noradrenaline receptors has now been extensively characterized at the structural and functional levels. Ligand binding and adenylyl cyclase activation studies helped define a beta-adrenergic profile that is quite distinct from that of the beta 1- and beta 2-adrenergic receptors, but strongly reminiscent of most of the "atypical" responses reported in earlier pharmacologic studies. Human, other large mammal, and rodent receptors share most of the characteristic beta 3 properties, although obvious species-specific differences have been identified. Recently, the incidence of a naturally occurring variant of the human beta 3-adrenergic receptor was shown to be correlated with hereditary obesity in Pima Indians and in Japanese individuals, and in Western obese patients with increased dynamic capacity to add on weight and develop non-insulin-dependent diabetes mellitus (NIDDM). A mild weight increase was also shown to develop in female, but not male, mice in which the beta 3 receptor gene was disrupted. Taken together, these results now provide a consistent picture of an important role of the beta 3-adrenoceptor in the regulation of lipid metabolism and as an obvious target for drugs to treat some forms of obesity.
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PMID:Structure and function of the beta 3-adrenergic receptor. 913 Dec 60

Adrenaline and noradrenaline, the main effectors of the sympathetic nervous system and adrenal medulla, respectively, are thought to control adiposity and energy balance through several mechanisms. They promote catabolism of triglycerides and glycogen, stimulate food intake when injected into the central nervous system, activate thermogenesis in brown adipose tissue, and regulate heat loss through modulation of peripheral vasoconstriction and piloerection. Thermogenesis in brown adipose tissue occurs in response to cold and overeating (diet induced), and there is an inverse relationship between diet-induced thermogenesis and obesity both in humans and in animal models. As a potential model for obesity, we generated mice that cannot synthesize noradrenaline or adrenaline by inactivating the gene that encodes dopamine beta-hydroxylase. These mice are cold intolerant because they have impaired peripheral vasoconstriction and are unable to induce thermogenesis in brown adipose tissue through uncoupling protein (UCP1). The mutants have increased food intake but do not become obese because their basal metabolic rate is also elevated. The unexpected increase in basal metabolic rate is not due to hyperthyroidism, compensation by the widely expressed uncoupling protein UCP2, or shivering.
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PMID:Thermoregulatory and metabolic phenotypes of mice lacking noradrenaline and adrenaline. 913 19


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